LOS ANGELES (AP) _ Violence in the city's South Central district sent shock waves across town Thursday, worrying people in pricier neighborhoods. Calls for more protection went unheeded by strapped private security companies.

Many people flocked to grocery stores to stock up on food before a dusk-to- dawn curfew that canceled sporting and cultural events a day after the acquittals of four officers in the Rodney King police beating case.

''I am busier now than I am at Christmas and Thanksgiving,'' said a Lucky market manager in Highland Park. ''We got every checkstand open and the lines are extremely long.''

Several Beverly Hills boutiques received threatening calls employees said were related to the acquittals.

''Most of us are pretty shaken up and nervous,'' said Charnee Long, the receptionist at Giorgio Armani on trendy Rodeo Drive, about 15 miles northwest of where the violence took place for a second day.

The store was evacuated briefly after a firebomb threat.

''He said he's going to burn our place down and we're in a lot of danger,'' she said. ''I just want to go home. With the richest white people here, we're definitely targeted.''

She sympathized with people's anger over the acquittals of four white policemen charged with assaulting King, a black motorist, but lameneted the looting and arson fires as unacceptable extremes.

Up the street at Ralph Lauren Polo, the manager said he got a crank call shortly after the verdicts were read Wednesday afternoon.

''We were among four other companies that had similar calls,'' said Svend Ingersle. ''It was a threatening-type of call that was related (to the King case).''

He said business was a little slow and the usual crowd of tourists that flock to trendy Beverly Hills had dwindled.

''I think a good portion of tourists are probably sitting in their hotels watching the news,'' he said.

At the Esprit clothing store in West Hollywood, employees came to work in the morning to find graffiti reading ''Kill LAPD'' and ''Guilty Cops'' scrawled on the outside walls. One large window was broken. Another had a bullet hole.

''It was pretty threatening graffiti,'' said manager Mara Bear, 29. She suggested the vandalism had little to do with the verdicts.

''So many kids they are getting excited and want to join in the fun. It's like an excuse,'' she said.

Calls to several overwhelmed security companies went unanswered. Howard Katz, president of Ace Security Service in Sepulveda, said he had no additional officers.

''Quite frankly, we are only working with our own customers, because we can't take jobs for only two or three days,'' she said. ''Where our customers have one car, they're asking for four.''

Mary Victor of Air Sea Land Security in Lomita said the company didn't want to send their guards out in the mayhem.

''It's too dangerous,'' she said.